Zappy is a legendary card having an average number of points and can cause splash damage. This is a relatively slow card and has to load his attack for 5 seconds. It can easily destroy everything in its path if you do not Counterbrake map early. The cost of 6 elixirs if the card can survive long enough to be easily profitable.
Zappy is a card that if left alone with a tower can easily destroy it with its powerful AoE. This is a card that can easily destroy a tank, as a Giant or Giant Royal few strokes.
How to counter Zappy?
Some cards are more suited to counter Zappy than others. To be effective, the cards must either allow or block Zappy force to recharge his attack or must be air troops are unlikely to be affected by damage to areas that apply only Zappy the ground.
So you can use:
Gargoyles: Zappy can destroy, but can easily be countered by fire spirits.
The Horde Gargoyles: to quickly destroy the Zappy if it is not forbidden.
The Army of Skeletons: A large number of skeletons can easily distract the Zappy and destroy it quickly.
The Hell Tour: to destroy Zappy with significant damage.
The Dragon of Hell, it is not affected by the attack Zappy and can, if the attack long enough to destroy it.
The Guards: to absorb the first attack Zappy and finish with the attacks of Skeletons.
Skeletons, Goblins, Barbarians: These three cards are used to enclose the Zappy and only one of them absorbs his attack when the other three are involved in the destruction. Be careful to place the cards.
Zap: to restore its zero to attack if the tower is already Zappy Arena.
Lightning: can stop the attack of the Zappy and cause much damage.
The Dark Prince: his shield can easily absorb the first shock and destroy Zappy after that.
The Prince: Only if Zappy has not already loaded his attack, his powerful attack can quickly destroy Zappy.
All these techniques allow you to effectively counter the Zappy. Obviously, there are other techniques and you sometimes you need to improvise during a fight as the cards you have in hand. Check out clash royale guide for more tips.